The antibiotic ristocetin A, described in U.S. Pat. No. 2,990,329 issued June 27, 1961, has been used in the treatment of infections caused by staphylococcus organisms and resistant to penicillin. The antibiotic vancomycin, described in U.S. Pat. No. 3,067,099 issued Dec. 4, 1962 is now used for the same purpose. Ristocetin has a favorable mode of action in that it is believed it interferes with synthesis of the bacterial wall by preventing the bacterial enzymes from acting on the substrate. Due to this mode of action, no bacterial resistance to ristocetin has developed. Ristocetin, however, is difficult to manufacture and has exhibited some toxicity.
Gram-negative micro-organisms are difficult to treat. It is known that they exclude the penetration of large molecules such as erythromycin antibiotic. It would therefore be desirable to develop an antibiotic which would retain the mechanism of action of ristocetin and at the same time be of smaller molecular weight and hence effective against gram-negative micro-organisms.